Answer:
13 seconds.
Step-by-step explanation:
Given

Required
Determine a reasonable solution for t
To do this, we equate h to 0.
becomes

Divide through by -4.9

Reorder the expression

Split
or 
This gives:
or 
But time can't be negative, So:

Answer:
15 minutes
Step-by-step explanation:
First, the motorcycle goes at a speed of 40 km/hr.
The question asks for how long it would take to travel 10 km.
Well, there are 60 minutes in an hour, since we will be translating into minutes.
Also, 10 km is 1/4 of 40 km, so it would make sense that the time length would be 1/4 of an hour as well.
1/4 of 60 minutes is 15 minutes. So it takes 15 minutes for the motorcycle to travel 10 km.
Now, if all this wordy stuff is too much to comprehend, you can also solve using proportional relationships.

Now cross multiply:

Divide both sides by 40:

Again, this shows that it wouls take 15 minutes for the motorcycle to travel 10 km.
Part a)
Identify the variable and categoriesBy reading the above statement, we can find that there are two variables and each variable has 2 categories. The variables and their categories are:
1) Class Number
This variable is further divided into 2 categories i.e. Class 9th and Class 10th.
2) Participation in Extracurricular activities
This variable is further divided into 2 categories based on if students participated or not.
Part b)Set up and fill 2 way table.Since, we have 2 variables and each variable has 2 categories the number of data cells will be 2 x 2 = 4 cells
There are total 100 students. 40 students are in class 10th. This means 60 students are in class 9th.Out of 40 students in class 10th, 18 students participate in at least one extracurricular activity. So remaining 22 students do not participate. 32 students from class 9th participate in extracurricular activities, this means the remaining 28 students do not participate. Based on this data, we can fill up the table as shown below
118 times
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