4. A circuit board uses three switches. We have three switches of type I, five of type II, and seven of type III. How many different choices are there?

105

Step-by-step explanation:

On the assumption that each switch must be a different type, we need to choose 1 type I switch from 2, 1 type II switch from 5 and 1 type III switch from 7.

The number of ways of picking objects from objects is

The total number of different choices =

If there's no restriction on the choices, we would need to pick 3 socks from a total of 15.

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:

after going and makeing graphs i would go with a,

there is nothing that is matches the graph. if there was i would show you. but therefore my answer is a.

hope i

-lavira: )