Answer:
475 mph
Step-by-step explanation:
Distance = rate × time
time = distance / rate
If x is the speed of the plane in still air:
2100 / (x + 25) = 1890 / (x − 25)
Cross multiply:
2100 (x − 25) = 1890 (x + 25)
Distribute and solve:
2100x − 52500 = 1890x + 47250
210x = 99750
x = 475
Answer:
The answer is 1.
Step-by-step explanation:
Nobel gases have full shell of valence electrons, that is why they tend to not enter any chemical reactions because they are satisfied while metals have very few electrons in the valence shell, so they are active in any chemical reaction.
If the number only has 2 digits, it could only be 91, because since the tens digit is 8 more than the ones digit, the tens digit is greater than or equal to 8. it cannot be 10 or more, because that would make the number over 100, leaving only 8 and 9. If the tens digit is 8, the ones digit is zero, and since it cannot be zero, then the tens digit must be 9, leaving the ones digit to be 1. So, the final answer is 91.