It might be c I'm not sure either. Hope I helped
Answer:
T = 1010 degree Celsius
Explanation:
mass of ball (Mb) = 100 g
mass of water (Mw) = 400 g
temp of water = 0 degree
specific heat of platinum (C) = 0.04 cal/g degree celsius
we can calculate the temperature of the furnace from the equation before
Mb x C x (temp of furnace (T) - equilibrium temp) = Mw x (equilibrium temp - temp of furnace)
100 x 0.04 x ( T - 10) = 400 x (10 - 0)
4 (T - 10) = 4000
T - 10 = 1000
T = 1010 degree Celsius
The cheetah's speed is 100x and
The gazelle's speed is 80x + 70.
Set the two equations equal to each other:
100x = 80x +70 (then subtract 80x from both sides).
20x = 70 (then divide by 20).
X =3.5.
The cheetah catches the gazelle after 3.5
Answer:

Explanation:
The textbooks say that the maximum range for projectile motion (with no air resistance) is 45 degrees.
To solve the problem it is necessary to use Newton's second law and statistical equilibrium equations.
According to Newton's second law we have to

where,
m= mass
g = gravitational acceleration
For the balance to break, there must be a mass M located at the right end.
We will define the mass m as the mass of the body, located in an equidistant center of the corners equal to 4m.
In this way, applying the static equilibrium equations, we have to sum up torques at point B,

Regarding the forces we have,

Re-arrange to find M,



Therefore the maximum additional mass you could place on the right hand end of the plank and have the plank still be at rest is 16.67Kg