You drive 6.0 km at 50 km/h and then another 6.0 km at 90 km/h. your average speed over the 12 km drive will be
(a) a greater than 70 km/h.
(b) less than 70 km/h.
(c) exactly 38 km/h.
(d) it cannot be determined from the information given because we must also know directions traveled.
(e) equal to 70 km/h.

The average speed is less than 70 km/h.

(B) is correct option.

Explanation:

Given that,

distance = 6.0 km

Speed = 50 km/h

Speed = 90 km/h

We need to calculate the time in 6.0 km distance

Using formula of time

Put the value in to the formula

We need to calculate the time in another distance

Using formula of time

Put the value in to the formula

We need to calculate the average speed

Using formula of average speed

Where, D = total distance

T = total time

Put the value into the formula

Hence, The average speed is less than 70 km/h.

305.7

explanation:

density =m/v

density =917/3.00

density = 305.

approximately = 305.7

in four significant figures