Part a: the sun produces 3.9 ⋅ 1033 ergs of radiant energy per second. how many ergs of radiant energy does the sun produce in 3.25 ⋅ 103 seconds? express your answer in scientific notation and show your work. (5 points) part b: which is the more reasonable measurement of the distance between the tracks on a railroad: 1.435 ⋅ 10−3 mm or 1.435 ⋅ 103 mm? justify your answer. (5 points) get

1.2675 * 10 ^ 37 ergs

Step-by-step explanation:

3.9 * 10^33  erg/s

how many ergs in 3.25 * 10^3 sec

3.9 * 10^33  erg/s * 3.25 * 10^3 sec

multiply the numbers, add the exponents

3.9 * 3.25 * 10^(33+3)

12.675 * 10^36

this is not in scientific notation  move the decimal 1 place to the left, which adds 1 to the exponent

1.2675 * 10^36+1

1.2675 * 10 ^ 37 ergs

1.435 ⋅ 10^3 mm

mm are  10 times smaller than cm

1 cm ≅ .04 inches

1 mm  ≅.04 inch

1.435 * 10 ^ -3 mm = .001435 mm  ≅  .001435 (.04) = .0000574  inches

1.435 ⋅ 103 mm  = 1435 mm ≅  1435*.04 =57.4 inches

57.4 inches /12 inches/ft  = 4.78 ft

This seems reasonable

i can you with this question sweetie!

step-by-step explanation:

hello from mrbilldoesmath!

answer:

25x^2 + 90x + 84

discussion:

mn(x) = m(n(x)) = m( 5x + 9) =

(5x + 9)^2 + 3 =>

25x^2 + 90x + 9^2 + 3 =

25x^2 + 90x + 84                 (as 9^2 = 9*9 = 81)

which is the second choice

regards,  

mrb

p.s.   i'll be on vacation from friday, dec 22 to jan 2, 2019. have a great new year!