Posts by scott
Total # Posts: 3,662

Math
chlorine is in Group 17 try the other side of the table 
physics
hey ... this works the gravitational potential energy of a object at a distance r from a large body is ... G M m / r the difference in the P.E. on the surface and at altitude is the K.E. at launch (G M m / r)  [G M m / (r + h)] = 1/2 m v^2 solve for h ... might be easier to ... 
physics
have you had calculus? the launch speed and low moon gravity means that the capsule goes beyond the region where g is relatively constant the force is related to the height by the universal gravitational equation ... f = G M m / (r + h)^2 force * height = energy ... ? de = ? f... 
Science
the compound H2O is broken into its constituent elements, hydrogen and oxygen 
Algebra
9 c  5(30  c) = 18 ... 14 c  150 = 18 
physics
g on the moon is 1.62 m/s^2 v^2 = 2gh ... h = v^2 / (2 g) 
chemistry
the volume is directly related to the absolute (Kelvin) temperature ... also called Charles' Law ... Kelvin temp = Celsius temp + 273 final volume = initial volume * [(final Kelvin temp) / (initial Kelvin temp)] 
Chem
you diluted a 210 ?M solution to 1/25 of its original 210 / 25 = 8.4 looks good 
Math
B + S + D = 93 B = 4S D = S  3 substituting ... (4 S) + S + (S  3) = 93 
Math
parallel lines have similar equations, but different x/y intercepts y = 2x + b plug in the given point to find b 
Math
looks good 
math
c = 2 i 7.8 i + 8.9 c = 1280 substituting ... 7.8 i + 8.9 (2i) = 1280 solve for i , then substitute back to find c 
Math
L  12' ? 2.88" 
physics
the berg is floating , so it has already displaced its mass in water melting won't change the water level 
math
M = 3/5 s M  20 = 2/5 (s  20) substituting ... 3/5 s  20 = 2/5 s  8 solve for s , then substitute back to find M 
Algebra 1
x at 10%, and y at 14% x + y = 10000 .10 x + .14 y = 1280 ... multiplying by 10 ... x  1.4y = 12800 adding equations (to eliminate x) ... .4 y = 2800 solve for y , then substitute back to find x 
math
3/5 d + [7/8 (2/5 d)] + 1 = d 3/5 d + 7/20 d + 1 = d 12/20 d + 7/20 d + 1 = d 
math
3/5 d + [7/8 (2/5 d)] + 1 = d 3/5 d + 7/20 d + 1 = d 12/20 d + 7/20 d + 1 = d 
Math IMPORTANT
length is not a property directly associated with a circle 
chemistry
pH + pOH = 14 pH + 9 = 14 ... pH = 5 log[H?] = 5 ... log[H?] = 5 ... [H?] = 1E5 pH < 7 means acidic 
Chem
the pressure is directly proportional to the absolute (Kelvin) temperature Kelvin = Celsius + 273 p = .989 atm * [(45 + 273) / (71 + 273)] 
Science
looks good 
Science
if you google "polygenic punnett square practice", you will see "Punnett square practice and examples" at "bifidosoft" it looks like a pretty good tutorial 
Chemistry
you have the letters mixed up search for GC/MS ... Gas chromatography–mass spectrometry 
chem
at constant temp and pressure, the volume is directly related to the number of moles added moles = new moles  7.51 mol = 7.51 [(15.9 / 4.11)  1] 
Maths
1.21 L W = x L * x W 1.21 = x^2 ... x = 1.1 ... a 10% increase 
exponential functions help please
it looks like if you multiply X by 4, you get Y that's linear ... not exponential 
Chem
the volume is directly proportional to the (absolute) temperature (ºK) and inversely proportional to the pressure v = 3.20 L * (1.50 / .989) * [(21.80 + 273) / (14.80 + 273)] 
Chem
the volume is inversely proportional to the ambient pressure v = 7.0 L * (765 / 725) 
Physics
work is energy is a scalar Wair = initial K.E.  final K.E.  m g h positive ... you are correct 
Trig
which of the functions is 1 at ?/2? 
MATH
isn't try B 
Math
B' is ... (2?2 , 2?2) 
chem
the volume is directly proportional to the ABSOLUTE (ºKelvin) temperature ... K = C + 273 v = 1.51E6 L * [(103 + 273) / (11 + 273)] 
Trigonometry
resolve the two vectors into x and y components add the respective components find the resultant vector 
Math
?(9x^2 24x +16) = 3x  4 
Chemistry
P = 5.00 mg * 1E5 % = 5.00E10 g P atoms = (5.00E10 / 31.0) * 6.02E23 
Maths
the equation is ... x + 24 = 36 after the semicolon is a space to fill in the xvalue of the solution ... x = _____ (12, in this case) 
algebra
7 < x < 4 
math
looks good 
Probability
there are 6^5 possible outcomes 6 of those have all the numbers the same 
Trigonometry
speed^2 = 2^2 + 5^2 ? is the angle downstream from directly across ... tan(?) = 2/5 
math
c is the combined time Shannon paints c/16, and Emily paints c/20 the two fractions add to 1 (the whole room) c/16 + c/20 = 1 ... 5c + 4c = 80 
Math: Area of Circles
area = ? r^2 = ? d^2 / 4 ? is pi ... 3.14159... 
Math
N = 1E6 (1  .05)^t 
Probability
p(outside) = 14/29 p(not visible) = 1/29 probability of two independent events is the product of the individual probabilities 
maths
w = 4 d (w  5)(d  5) = 175 (4 d  5)(d  5) = 175 ... 4 d^2  25 d  150 = 0 use quadratic formula to find d ... then substitute back to find w 
Probability
there are 6^3 ways to travel on the three days walking on one day leaves 5^2 options for the other two p = (3 * 5^2) / (6^3) 
Math
Reiny following your pattern; if x^n is the largest term , then there are 2n+1 terms the (increasing) term coefficients are one greater than their corresponding exponent you're missing some terms/coefficients in the squaring of the smaller polynomial the easycalculation ... 
Math
google "polynomial multiplier calculator" use the easycalculation application 
Science
the moon's mass is about 1/6 of earth, so the gravitational potential energy is also about 1/6 
Physics
momentum is conserved, and energy in an elastic collision up is positive (50 * 4.0)  (.45 * 30) = (50 p) + (.45 b) ... 186.5 = 50 p + .45 b 1/2 [(50 * 4.0^2)+(.45 * 30^2)] = ... 1/2 [(50 * p^2)+(.45 * b^2)] ... 1205 = 50 p^2 + .45 b^2 solve the system of equations for b ... ... 
math
28 * 1 1/4 = 35 2 1/2 * 12 = 30 (35  30)/ 1 1/4 ... on another shelf 
math
a. (4 * 1) + (5 * 2) = 14 = .875 p b. 10  5  4 = ? c. .125 p 
Math
x^26x+9 is already a perfect square ... (x3)^2 an equation is needed for a solution 
Science (Last question of these)
momentum is conserved right is positive (10 * 20)  (B * 20) = (B * 0)  (10 * 20) 2(10 * 20) = B * 20 
Math 302
6C3 * 5C4 
Math 302
A. 150^3 B. 150 * 149 * 148 
math
160 / 4 = 40 41 , 39 , 43 , 37 
Alg I
arithmetic ... the difference is 6 (1536  12) / 6 = ? 12 is the 2nd term ... 1536 is the (?+2) term geometric ... the ratio is 2 12 * 2^? = 1536 1536 is the (? + 2) term 
maths
2y + 5x = 4 2y = 5x + 4 y = 2.5x + 2 algebra, right?? 
maths
I answered that correctly 2/25 1:34pm why do you think it was wrong 
physic
f = m a net force = [(8m/s^2)/(2.26 kg)]i + [(6m/s^2)/(2.26 kg)]j subtract F1 and F2 from the net force to find F3 
Trig Math
C = 25000 cos(?) plug in the various values of ? to find the corresponding C 
science
force equals mass times acceleration force is directly proportional to both quantities 
Algebra 1
x = 6 + 2 (6 + 2)^3  1 = ? 
Algebra
the profit is the difference between the student fees and the studio rental cost P = (N * F)  C F = (P + C) / N 
Math
t = 1161.87  (1161.87 / 1.02) 
math
[87 (p  1)] + 82 = 86 p 
math
P E M D A S 
Math
halving the height, halves the volume doubling the radius, quadruples the volume 1/2 * 4 = 2 ... volume is doubled 
Algebra
for annual compounding total value = initial (1 + interest)^years t.v. = 2800 (1 + .0265)^7 
Chemistry
NO ... not one of the choices ... remember the sig fig hint 
Chemistry
2.10 * 530 * (15.0  45.0) = ? J careful with sig fig 
math
m  m/3  5  3/5(m  m/3  5)  9 = 45 m  m/3  3m/5 + m/5 = 56 15m  5m  9m + 3m = 840 
Physics
oops...got the fraction inverted 
Physics
accel = force / mass = 32 / 20 = 1.6 m/s^2 (9.0 m/s  4.0 m/s) / 1.6 m/s^2 = ? s 
Physics
3.6 / .45 = ? hz 
Algebra
J = a/2  3 
Maths
200% more means three times as large the length and width of the projector screen are three times the length and width of the television screen this means the area of the larger screen is nine times the area of the smaller nine times means 800% more 
math
mag = ?[(7  4)^2 + (3  1)^2] tan(?) = (3  1) / (7  4) ... Quad II 
maths
easy technique for this format of problem swap the coefficients ... 2y  5x = ? change one sign ... 2y + 5x = ? plug in point ... 2(7) + 5(2) = 14  10 = 4 equation is ... 2y + 5x = 4 
APB Physics
2.00 rad/s * 1.7 s = ? rad 
Physics
work = force * distance = 30 N * 6 m ... answer is in Joules work = m g h = 50 * 9.8 * 300 
Perimeter and fraction,Grade 6th Maths
perimeter = 2 length + 2 breadth 80 = (2 * 32) + 2 breadth 80 = 64 + 2 breadth 16 = 2 breadth ... 8 = breadth 
Science
A. K.E. = 1/2 * mass * (velocity)^2 B. work and energy are the same thing ... measured in Joules 
Math
looks good 
Math
D = k v^2 ... 90 = k * 70^2 ... k = 9 / 490 D = (9/490) * 71^2 
physical science
force times distance equals work (energy) 
physical scienceasap
work (energy) = force * distance 10 J = 10 N * ? 
Math
looks good 
Physics
momentum is conserved the mass is doubled, so the velocity components are halved ... 1 m/s N and 5 m/s E magnitude of v ... v^2 = 1^2 + 5^2 direction ... tan(?) = 1 / 5 ... ? is the angle north of east 
Math
R = .1639 V^2 R = .1639 * 215^2 
physics
the tension in the string provides a horizontal force of 5.8 lb, and a vertical force of 10 lb tan(?) = 10 / 5.8 
Math
A = k B^2 a) 45 = k * 3^2 ... k = ? b) A = ? B^2 c) A = ? * 6^2 
physic
f = G * M1 * M2 / r^2 7.30E25 = 6.67E11 * M1 * M2 / 1.50E12^2 solve for (M1 * M2) M1 + M2 = 6.00E30 substitute to find M1 and M2 
algebra 2
f(x) = (x + 1)(x + 1)(x  6) multiply the binomials 
Math
yes 
Science
the gravitational attraction of the masses is what holds the moon in orbit gravity provides the centripetal force for the circular (mostly) path 
Geometry
you're doing fine plug in all the numbers you have, and solve for the missing side (the only nonnumber)