The stone tool industry being described is the Acheulean. These tools are characterized by hand axes and bifacial blades and were made by many different species of Homos, including Homo erectus and early Homo sapiens.
Answer:
A) 
B) 
Explanation:
Given:
mass of car, 
A)
frequency of spring oscillation, 
We knkow the formula for spring oscillation frequency:




Now as we know that the springs are in parallel and their stiffness constant gets added up in parallel.
<u>So, the stiffness of each spring is (as they are identical):</u>



B)
given that 4 passengers of mass 70 kg each are in the car, then the oscillation frequency:



Answer:
denoting, relating to, or operated by a liquid moving in a confined space under pressure.
Answer:
True
Explanation:
A crowbar makes our work easier by multiply effort because it belongs to first class lever.
And first class lever makes work easier by multiplying the effort