m？

So now each set needs (6/x- 1/55)m? , you can make (x+3) sets.

The equation is: (6/x- 1/55)*(x+3)=6.

The solution is x=30.

So now you can make 33 sets.

2. Party A needs X days and Party B needs Y days.

Then the speed of a is 1/x, and the speed of b is1/y.

According to the condition1:(1/x+1/y) * 4+1/y.

*5= 1

According to condition 2: x=y-5.

X= 10，y= 15。

3. Let everyone's speed be V and the total workload be 1.

Then v= 1/mn.

Now there are m+5 people, the speed is still 1/mn, the workload is 1, and the time required is t.

Then (m+5)*( 1/mn)*t= 1.

T=mn/(m+5)

4. Suppose it takes t years to develop the land area of V every year.

T*v=360。

Now the time is reduced by 6 years, and the area of developed land is increased by 2㎡ every year, and the total development area is considered as 360.

That is, (t-6)*(v+2)=360.

The solution is t=36,

v= 10

Then the actual development is12m2.