if you drive 30 miles in 40 minutes, and then 15 miles in 20 minutes, do you have a constant speed?

a) yes

b) no

c) maybe, depending on the instantaneous speed at each instant of the trip

d) maybe, depending on the car

A) yes

Explanation:

First section of trip: 30 miles in 40 minutes

Second section of trip: 15 miles in 20 minutes

The formula for speed is distance over time

Calculate the speeds for each section of the trip.

First:

k = d/t

k = 30miles/40minutes  <= reduce fraction by 10 (30÷10 and 40÷10)

k = 3 miles / 4 minutes

Second:

k = d/t

k = 15miles/20minutes  <= reduce fraction by 5 (15÷5 and 20÷5)

k = 3 miles / 4 minutes

Therefore there is a constant speed because both sections of the trip are driving at "3 miles / 4 minutes".

3 miles / 4 minutes can be also formatted as:

0.75 miles per minute.

it about 600 mph from what i calculated

a

explanation:

no diagram was provided, but i'm guessing it's the one i've attached to my answer.

here, a mechanical force turns the rod.   this generates an electric current in the coil, which powers the bulb.