Turn off standby appliances.
Install a smart thermostat.
Turn down your thermostat.
Buy efficient appliances.
Install a new boiler.
Wash clothes at a lower temperature.
Be smarter about water.
Invest in double glazing.
Answer:

Explanation:
The correct equation follows the law of conservation of energy where kinetic energy is all transformed to potential energy, since we know that kinetic energy is expressed as
while potential energy is mgh where m is the mass of the object, v is the velocity or speed of the object, g is acceleration due to gravity and h is the vertical height. Therefore, relating the two equations we should have 
Answer:
v=3.66,h-3.66
Explanation:
vertical = 10sin60 - 10sin 30
horizontal =10cos60 + 10cos 30
v = 10×0.8660-10×0.5
h = 10×0.5 + 10 × 0.8660
v=8.660-5.0 = 3.66
h= 5.0-8.660 = -3.66
Newton's 2nd law of motion:
Force = (mass) x (acceleration)
= (0.314 kg) x (164 m/s²)
= 51.5 newtons
(about 11.6 pounds) .
Notice that the ball is only accelerating while it's in contact with the racket.
The instant the ball loses contact with the racket, it stops accelerating, and
sails off in a straight line at whatever speed it had when it left the strings.