(ii) Round off the number of seconds in an hour to 1 significant figure.
4000

A plane travels at a speed of 212 mph.
b) By rounding 212 to 1 significant figure and using your answer
to part (ii), work out an estimate for the number of seconds the plane
takes to travel 1 mile.

Total marks: 4

The number of seconds in an hour to 1 significant figure is 1.1111.

The number of seconds the plane  takes to travel 1 mile is 16.98 seconds.

We have to determine, the number of seconds in an hour to 1 significant figure.

And the number of seconds the plane  takes to travel 1 mile.

According to the question,

1. Number of seconds = 4000

The number of seconds in an hour is,

Therefore,

The number of seconds in an hour to 1 significant figure.

Hence, The number of seconds in an hour to 1 significant figure is 1.1111.

2. A plane travels at a speed of 212 mph,

The number of seconds in an hour is,

Therefore,

The number of seconds the plane  takes to travel 1 mile is,

Hence, The number of seconds the plane  takes to travel 1 mile in 16.98 seconds.

For more details refer to the link given below.

link

see below

Step-by-step explanation:

(ii)

Given 4000 seconds to hours you divide the value by 3600 sec

=4000/3600 =1.1111

=1.0 hour (1 significant figure)

(b)

speed = 212 miles/hour

distance= 1 mile

time = distance/speed = 1/212 * 3600 =16.98 seconds

let's cover over the formula of the vertex:

y = a(x – h)^2 + k

in this formula, (h,k) are the vertex, always remember that the positive or negative value of the vertex is based on the sign it has.

for example, if the vertex is -3,-6 then both the x and y value would have the positive sign attached to it and if it were a positive x and y value, then a negative sign would be attached to it.

with that being said, for our problem the x value is a positive one so we are looking for a number with a negative sign next to it, in this case the first and second choice.

however, for the first answer choice it isn't quite part of the formula so we know that the answer choice correctly displays the x value.

to confirm, we can see if the -1 fits correctly with the second answer choice, and as mentioned above a negative number will have a positive sign attached to it. so, for our problem we can see that -1 has been changed to +1, so we can confirm that the second answer choice is correct.

hence, our final answer is y=(x - 1)^2 + 1

answer: 4 meters

step-by-step explanation: to you understand 2/3 better you can do 1 divided by 3 = . then multiply that by the 2 which is .66666666666666667 then you would do 6 x .66666666666666667 which is 4.      

hope this .