Which of the following statements is/are correct? 1. atoms are the smallest particles of an element that retain the element's chemical properties. 2. substances composed of only one type of atom are classified as elements. 3. of the 118 known elements, only 48 occur naturally.

1. Atoms are the smallest particles of an element that retain the element's chemical properties.

2. Substances composed of only one type of atom are classified as elements.

Explanation:

Statement 3 is wrong because out of the 118 identified elements, the first 94 of them occur naturally on Earth and the remaining 24 are synthetic elements.

no. dot product   =0 when vecs at right angles

when a device is used in a circuit in which the voltage is 81 v, the current flowing through the device is 3 a. what is the resistance of the device?

a. 27 ω

b. 40.5 a

c. 243 ω

d. 243 a

the correct answer is a. 27