Answer:
Number of revolution made by tire is 1.57 x 10⁷
Explanation:
Radius of tire, r = 0.220 m
Circumference of tire, C = 2πr
Substitute the value of r in the above equation.
C = 2 x π x 0.220 m = 1.38 m
Total distance covered by tire in a year, D = 13500 miles
But 1 mile = 1609.34 m
So, D = 13500 x 1609.34 m
Number of revolutions take by tire, N = 

N = 15743543
Answer:a
Explanation:
We have to lift the load two loads up one story, so energy required is
let m be the mass of each load and h is the height of each story
Energy 

Here energy gained is the potential energy which depends upon the datum(floor).
For lifting one load up one story
Energy required

thus
is half of 
So option a is correct
substitution is the type of mutation that occurred
Answer:
9.8kW
Explanation:
Given data
Mass= 60kg
Hieght= 4m
Time= 4.2seconds
We know that the energy possessed is given as
PE=mgh
PE=60*9.81*4
PE= 2354.4 Joulse
Also, the expression for power is
Power=Energy*Time
Power= 2354.4*4.2
Power=9888.48 watt
Power= 9.8kW