A and B working alone can finish a task in 12 and 16 days respectively. In how many days can the task be finished if they work for one day each alternatively, and A begins the work?
12 \( \frac{1}{3} \)days
12 \( \frac{2}{3} \) days
13 \( \frac{1}{3} \) days
13 \( \frac{2}{3} \) days
(\(\sqrt{5}\) + \(\sqrt{7}\))² is a:
In order to celebrate earth's environment and raise public awareness about pollution, which of the following days is observed worldwide as Earth Day each year?