An electric field from a charge has a magnitude of 4. 5.

Of four agents alpha, beta, gamma anddelta, three have to be sent together on amission. if alpha and beta cannot gotogether, beta and gamma cannot go togetherand gamma and delta cannot go together, then which of the following holds? 1. any three agents can be sent.2. alpha, delta and any one out of beta andv gamma can be sent.3. beta, gamma and any one out of alphaand delta can be sent.4. the mission is impossible.

If (a, b) is the solution to the system of equations shown above, and a and b are integers, then what is the value of a+b?

What percentage of the earth's water is available for use by living things?