Answer:
The Event Horizon Telescope comprises of a an interconnection of radio observatories. These radio observatories work in unison and helps in efficient observation of radio sources associated with black holes with angular resolution in comparison to their event horizons. This equipment functions by ensuring that anything or light which goes through the event horizon cannot escape from the black hole. Instead there will be a continual falling towards the center of the black hole.
Power is a measure of the rate at which work is done. Power is determined by the change in energy
We will define the Total mass to calculate the force, so our values are:
Total Mass 
The Weight is,

Through the hook's Law we calculate X.
, where x is the lenght of compression and K the Spring constant.
We don't have a K-Spring, but we can assume a random value (or simply let the equation in function of K)

I assume a value of 

Answer:
(a) 98.548 mPa
(b) N = 942346
9.42 X 10∧5 cycles
Explanation:
The solved solution is in the attach document.
Answer:
Ví dụ 1 : Hai vật xuất phát từ A và B cách nhau 400m chuyển động cùng chiều theo hướng từ A đến B. Vật thứ nhất chuyển động đều từ A với vận tốc 36km/h. Vật thứ hai chuyển động đều từ B với vận tốc 18km/h. Sau bao lâu hai vật gặp nhau ? Gặp nhau chỗ nào