Which vanable expression represents the word phrase?
the sum of 12 and the quotient of 9 and a number
o 9+(12 + y)
o 12 - (9 = y)
o 12 - 9
12 + (97)

b). 4320 have a nice day

explanation:

infrared radiation has wavelength in the range between 700 nm and 1 mm. lets' convert these values into scientific notation, keeping in mind that:

let's start from the lower value, we have:

(we moved the dot two places to the left, so we increased the exponent by 2 units, from -9 to -7)

the higher value is:

so, the range of wavelength of infrared radiation is: