Math problems, who knows? Thanks, math questions, who will? Yes, help me out,

It's so hard. Call your teacher to teach you.

A: variance = [(60-75)2+(65-75)2+(75-75)2+(75-75)2+(80-75)2+(95-75)2=(225+100+0+0+25+400)=125, the mode is 75, and the difference between the maximum and minimum values is 95-60=35

The mean of B is 1 6 (85 + 70 + 70 + 75 + 70 + 80) = 75 and the median is 1 2 (70 + 75) =

If the mode is 70, the mean and variance are combined, and student B's grades are more stable.

Judging from the trend, A's performance is more stable, and B's is more volatile.

In the question, it is said that about y-axis symmetry, because the form that becomes cos x is an even function, and it can be symmetrical about the y-axis, so we have to make sin become cos, because "odd and even are unchanged", so let 2 + 6 be an odd multiple of 2, that is, 2 + 6 = 2 + k

Divide by equals 5.

A: I can make 5 sets.

(1) x 2-3x+2≠0 solution gives x≠1, x≠2 (2) 1-x 2 0 and x≠0 solution gives -1 x 1 and x≠0 (3) 2x+ 4≠k + 2 gives x≠k 2+ 8 (k=0,1,2,3...

4) -1 x +3 1 gets -4 x -2

Take one of the middle 8s on the right side of the equation to the left side of the 1 on the left side of the equation and become:

<> use the bridge to match the width of the specified accumulation of socks to calculate.

Picture friends disturb Chang and pick up Li Ye.

1, -30 - 30 = -60 (meters).

The height of the benthic fauna is 60 meters.

2．-|1|= -1, the opposite number is 1

-3-1 8) = 3+1 8 = 25 8, the reciprocal is 8 25

3, these 2 dots represent the number and 2 5

4, -1 + 8 - 10 = -3 (degrees). The temperature at night is 3 degrees 59.6 million = 9600000 = [km 2], which is written in scientific notation as about square kilometers.

1.- 60 meters.

5.Tilting his neck and looking at it for a long time, Adopt me