Answer:
Explanation:
Using the efficiency formula;
Efficiency = Work done by the machine (output)/work done on the machine (input) ×100%
Efficiency =w/50 ×100
90 = 100w/50
Cross multiply
90×50 = 100W
4500 = 100W
W = 4500/100
W = 45Joules
Hence the lever does 45Joules of work on its load
2) Mechanical Advantage= Load/Effort
Given
MA = 4
Load = 500N
4 = 500/Effort
Effort = 500/4
Effort =125N
Hence the effort required to lift the load is 125N
A synthesis reaction occurs when a molecule is formed from the bonding of atoms, ions or simpler molecules. A single product is created from multiple reactants. These reactions are exothermic since they release energy in the form of light and heat.
Answer:

= average acceleration
= final velocity
= starting velocity
= elapsed time
Explanation:
Please give me brainliest :)