For the first question, you got them right, for the two you left blank, initial(beginning) velocity: 2 m/s the final velocity is: 12 m/s
The quantity of heat must be removed is 1600 cal or 1,6 kcal.
<h3>Explanation : </h3>
From the question we will know if the condition of ice is at the latent point. So, the heat level not affect the temperature, but it can change the object existence. So, for the formula we can use.

If :
- Q = heat of latent (cal or J )
- m = mass of the thing (g or kg)
- L = latent coefficient (cal/g or J/kg)
<h3>Steps : </h3>
If :
- m = mass of water = 20 g => its easier if we use kal/g°C
- L = latent coefficient = 80 cal/g
Q = ... ?
Answer :

So, the quantity of heat must be removed is 1600 cal or 1,6 kcal.
<u>Subject : Physics </u>
<u>Subject : Physics Keyword : Heat of latent</u>
The velocity is 6.75
The velocity in the equation stated above can be calculated as follows
m= 2,000
p= 2.25
y= 6000
velocity= 2.25 × 6000/ 2000
= 13500/2000
= 6.75
Hence the velocity is 6.75
Please see the link below for more information.
brainly.com/question/23547288?referrer=searchResults
Answer:
Three advantages of Reflecting Telescope over refracting Telescope:
1. there is no chromatic aberration in the Reflecting Telescope being mirror as an objective, while Refracting Telescope can suffer chromatic aberration being using lenses.
2. image of Reflecting Telescope is brighter due to large, polished curved mirrors than Refracting Telescope
3. Reflecting Telescope is compact and portable in size than Refracting Telescope.
Density: 1.9 g/cm3
density = mass/volume
d = 5.7/3
d = 1.9