Which of the following forces is responsible for keeping the planets in orbit around the sun?

question 3 options:

a. friction

b. electromagnetic force

c. magnetism

d. gravity

plz i need : 3

this could be newton#'s law of cooling. the cooling curve is exponential

i had this question and the answer was 3.15 miles.

martina travels from school to her mom's office. from there, she walks to school. after school, she walks to the library and then to a friends house before finally ending back at home. find martina's total distance traveled.

a) 0 miles  

b) 0.4 miles  

c) 1 mile  

d) 3.15 miles