What is the condition of the outside air at a certain time and place?

The blackbody curve for a star name zeta is shown below. what is the peak wavelength for this star ?

If e is the symbol for an element, which two of the following symbols represent isotopes of the same element? 1. e2. e3. ea.1 and 2c.1 and 4b.3 and 4d.2 and 3

Of the following elements, which is the least reactive? a. c b. h c. li d. he