(a) It increased by $0.30 each day for 10 days, or an increase of $3.00
(b) Over the next 10 days, it decreased by 10*0.45 = -$4.50
(c) The last 10 days, it changed by 10*.25 = $2.50
(d) You correctly came up with a total change of 0.1 but that is correct only because each period was the same length. If there had been different lengths of time, the result would have been different. The average daily change over the full 30 days is (total change)/(no. days) = $1.00/30 = $0.033/day.
(e) Since the net change was positive, it appears to be a good buy. However, you have to consider taxes and commissions, so it might not have been the best use for your money. On the other hand, it depends on the stock price.
If it was $IBM, at $150/share, a net increase of $1.00 isn't much.
If it was a penny stock, trading at $0.75/share, then the change is a significant percentage.
It also depends on how many shares you're trading. A huge number of shares might affect your decision.
Also, the stock seems to be bouncing around, so I'd steer clear of it, unless this is just a wiggle in what appears to be a long-term increase.
Stock trading can get complicated!!