Answer:
There was 32.5mm of rainfall on the seventh day.
Step-by-step explanation:
Mean of a data-set:
The mean of a data-set is the sum of all values of a data-set divided by the number of values in the data-set.
The mean daily rainfall for a week was 5.5mm.for the first six days the mean rainfall was 1mm.
This means that during the week(7 days), the total amount of rain was of:

How much rainfall on the seventh day ?
This is x. We have that:




There was 32.5mm of rainfall on the seventh day.
3, because when you both square and square root a value the two cancel each other out.
Answer:
um try to type it out bc that made no sense
Step-by-step explanation:



At

, you have

The trick to finding out the sign of this is to figure out between which multiples of

the value of

lies.
We know that

whenever

, and that

whenever

, where

.
We have

which is to say that

, an interval that is equivalent modulo

to the interval

.
So what we know is that

corresponds to the measure of an angle that lies in the third quadrant, where both cosine and sine are negative.
This means

, so

is decreasing when

.
Now, the second derivative has the value

Both

and

are negative, so we're essentially computing the sum of a negative number and a positive number. Given that

for

, and

for

, we can use a similar argument to establish in which half of the third quadrant the angle

lies. You'll find that the sine term is much larger, so that the second derivative is positive, which means

is concave up when

.