If earth were twice as massive but it revolved at the same distance from the sun, its orbital period would be

a) 1 year.
b) 3 years.
c) 2 years.
d) 4 years.
e) 6 months.

A) 1 Year, if the Earth is larger in mass, but still the same distance from the sun, it will orbit at the same rate.

one person pulls 90n one way and the other has 100n pulling the other way.

so the net force = 90 - 100 = -10n,

or the ans can be 10n if the picture shows -90n and 100n instead.

the old price per ounce is c/4.

the new price per ounce is c/3.6.

the ratio of the old price to the new one is

(c/4)/(c/3.6) = (c/c)×(3.6/4) = 0.9 . . = 9/10 . . "nine tenths" in either form