Answer: 8.1e+2 or 8.1E+2 (in the scientific notation mode), based on that the number given is 8.1 × 10².
Explanation
Scientific calculators use the letter e or E to show the numbers in scientific notation mode.
These are some examples of numbers that require scientific notation and how they are shown.
Number Scientific calculator display
6.022 × 10²³ 6.022 e+23
5 × 10 -12 5 E -12
So, understanding that your question is about number 8.1 × 10², the scientific calculator could show 8e+2.
Nevertheless, since 8 .1 × 10² is 810, not a long number, if the display is not in scientific notation mode, it could just display just 810,
Answer:
31395 J
Explanation:
Given data:
mass of water = 150 g
Initial temperature = 25 °C
Final temperature = 75 °C
Energy absorbed = ?
Solution:
Formula:
q = m . c . ΔT
we know that specific heat of water is 4.186 J/g.°C
ΔT = final temperature - initial temperature
ΔT = 75 °C - 25 °C
ΔT = 50 °C
now we will put the values in formula
q = m . c . ΔT
q = 150 g × 4.186 J/g.°C × 50 °C
q = 31395 J
so, 150 g of water need to absorb 31395 J of energy to raise the temperature from 25°C to 75 °C .
Answer:
The probability of spinning red with the spinner or rolling an odd number with the die is 
Explanation:
Given that,
Total color in spinner = 4
Let the area of four parts is equal in the spinner.
We need to calculate the probability of spinning red
Using formula of probability

Put the value into the formula

We need to calculate the probability of odd number of the die
Using formula of probability

Put the value into the formula


We need to calculate the probability of spinning red with the spinner or rolling an odd number with the die
Using formula of probability of two events which is independent

Put the value into the formula


Hence, The probability of spinning red with the spinner or rolling an odd number with the die is 
D will because water just turns from liquid to a gas by adding heat. That is a physical change. The other equations are chemical changes.