Thes are all correct :<span>2.Scientists observe natural events occurring around them. They question these observations and investigate them.
3.All scientists follow one scientific method of investigation
4.If a hypothesis is not verified by the results from the scientific method, scientists may either redo the process or create a new hypothesis.</span>
Answer: 7.5 rev/s
Explanation:
We are given the angular velocity 
a helicopter's main rotor blades:
However, we are asked to express this in the International Systrm (SI) units. In this sense, the SI unit for time is second (
):
Answer:
juz taking points nvm no sry for u cos u too wasted point
Answer:
65
Explanation:
The resonant frequencies for a fixed string is given by the formula nv/(2L).
Where n is the multiple
.
v is speed in m/s
.
The difference between any two resonant frequencies is given by v/(2L)= fn+1 – fn
fundamental frequency means n=1
i.e fn+1 – fn = 390 -325
= 65
