Aslow jogger runs a mile in 13 min. calculate speed in. a) in/s b) km/h
(1mi=1609m); (1in=2.54),

a) 81.23 in per second  ,  b) 7.44 km / hour.

Step-by-step explanation:

Given: a slow jogger runs a mile in 13 min.

To find: Calculate speed in. a) in/s b) Km/h

Solution : We have given that jogger runs  1 mile = 13 min.

We know that  1 mile = 63360 inches

i minute = 60 second

Then Speed =  

Then Speed =  

a ) In inches / second

Plug   1 mile = 63360 inches

13 mint = 780 second

Speed =  

Speed = 81.23 in per second .

b) For km/h

Given 1 mile = 1609 m

1 kilometer =  1000 meter

1 mile = 1.609 km

1 hour = 60 mint

1 mint = 1/60

13 mint = .

13 mint= 0.216 hour

Then Speed = Speed =  

Speed = 7.44 km / hour.

Therefore, a) 81.23 in per second  ,  b) 7.44 km / hour.

it could 14.28 but if its not that one then it has to be the 17 one. hope this ! : )

step-by-step explanation:

reduce the friction between its moving parts

step-by-step explanation:

in fact, by reducing the friction between the moving parts of the machine, it is possible to reduce the energy wasted due to this friction; therefore, more input energy is converted into useful work, and this will improve the efficiency of the machine.