Answer:
A. Speed
Explanation:
A vector quantity is a quantity which has both magnitude and direction. Here in the given options, speed is a scalar quantity but not the vector quantity.
Answer:
37.34372 kg
Explanation:
m = Mass
= Change in temperature
1 denotes water
2 denotes copper
c = Heat capacity
Heat is given by

In this case the heat transfer will be equal

Mass of copper block is 37.34372 kg
When A Light Ray Hits A Boundary,,,,, it is called refraction.
Answer:
<h2>45.68 g</h2>
Explanation:
Given 45.678 g, converting the value to 4 digits is similar to converting the decimal number to 4 significant figure. We can see that the decimal number initially contains 5 numbers. To covert to a 4 digits number we will convert the last digit which is 8 to 0 because 0 is insignificant.
If the number we are converting to zero is more than 4 then the preceding number (7) will be rounded up by adding 1 to it
The decimal number will become 45.68.
Note that the value of 7 was rounded up to 8 since the value we are converting to zero is more than 4.
<em>Hence the decimal value in 4 digits is 45.68 g</em>