Answer:
B. z has a negative charge
Step-by-step explanation:
Answer:
6.21 seconds
Step-by-step explanation:
The position function of a free-falling object is,

Where,
= initial height of the object,
= initial velocity of the object,
Here,


Hence, the height of the ball after t seconds,

When s(t) = 0,




∵ Time cannot be negative,
Hence, after 6.21 seconds the ball will reach the ground.
Given that I no not see any explanation in the previos answer, I think you can benefit of this.
Exothermic refers only to the fact that the reaction releases energy in the form of heat when occurs. So, the enthalpy is higher at start and lower and the end.
Seen in this way, you can deduct that the change in enthalpy is negative, which is what the third option says.
Answer:
B
Step-by-step explanation:
Answer:
38.5
Step-by-step explanation:
Lets say, first number = x
Second number = 3x+7
Total = 49
(x)+(3x+7)= 49
4x+7 = 49
4x = 42
x = 42/4
x= 10.5
x= 10.5
3x+7 = 3(10.5)+7 = 38.5
Hope this helps!!