Answer:
a)  fr = 224.3 N
, b)   fr = 224.3 N
, c)   v = 198.0  m/s
Explanation:
a) For this exercise let's start by calculating the acceleration in the fall
              v² = v₀² - 2 a (y-y₀)
When it jumps the initial vertical speed is zero
              a = -v² / 2 (y-y₀)
              a = -68 2/2 (1000-2000)
              a = 2,312 m / s²
Let's use the second net law to enter the average friction force
             fr = m a
             fr = 97 2,312
             fr = 224.3 N
b) let's look for acceleration
             v² = v₀² - 2 a y
             a = (v² –v₀²) / 2 (y-y₀)
             a = (4² - 68²) / 2 (0-1000)
             a = 2,304 m / s²
             fr = m a
             fr = 97 2,304
             fr = 223.5 N
c) the speed of the wallet is searched with kinematics
            v² = v₀² - 2 g (y-y₀)
            v = √ (0-2 9.8 (0-2000))
            v = 198.0  m/s
 
        
             
        
        
        
The answer is going to be element #29 Copper makes blue 
Red:#38 
Green:#56
Pink:#3
Yellow:#11
Gold:#20
Hopes This Helps 
        
                    
             
        
        
        
Answer:
Yes the valency of oxygen is 2
 
        
             
        
        
        
Answer:
Basketball 
Explanation:
Basketball was invented to keep athletes warm in the winter.
 
        
                    
             
        
        
        
Answer:
P_(pump) = 98,000 Pa
Explanation:
We are given;
h2 = 30m
h1 = 20m
Density; ρ = 1000 kg/m³
First of all, we know that the sum of the pressures in the tank and the pump is equal to that of the Nozzle,
Thus, it can be expressed as;
P_(tank)+ P_(pump) = P_(nozzle) 
Now, the pressure would be given by;
P = ρgh
So, 
ρgh_1 + P_(pump) = ρgh_2
Thus,
P_(pump) = ρg(h_2 - h_1)
Plugging in the relevant values to obtain;
P_(pump) = 1000•9.8(30 - 20)
P_(pump) = 98,000 Pa