中一升中二英文數學[[求救]]

１A man invents $1000000 in a fund. The value of the investment grows by 5% each month
a.What is the value of the investment afterthe first month?
1000000(1+5%) = 1050000

b.What is the value of the investment after four months?
1000000(1+5%) ^4 = 1215506.25

c.In the fifth month, the investment loses 20% of its value. Does the man gain or lose over a five-month period? What is the percentage gain or loss?
1215506.25(1-20%) = 972405
loss
percentag loss = (972405 - 1000000) / 1000000 * 100% = -2.7595%
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**２What are the mistakes in the following calculations?
a. (1,1)+(2,2)=(3,3)
b. (3,2)- (1,0)=(2,2)
無錯 ....
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**３What is the range of value of 29.97 x 39.95 +198.8 - 204.3 ?
A.1100-1200 B.1000-1100
C.900-1000 D.800-900
29.97 x 39.95 +198.8 - 204.3 = 1191.8015
A.1100-1200