The electron configuration of an element is 1s22s2. How many valence electrons does the element have? (1 point) a 1 b 2 c 3 d 4

At the current rate, a graph of carbon dioxide produced by fossil fuels over time would slope upward slope downward be horizontal be vertical

Which one of the following is an oxidation-reduction reaction? naoh + hno3 --> h2o + kno3 naoh + hno3 --> h2o + kno3 so3 + h2o --> h2so4 cacl2 + na2co3 --> caco3 + 2 nacl ch4 + 2 o2 --> co2 + 2 h2o al2(so4)3 + 6 koh --> 2 al(oh)3 + 3 k2so4

Can anyone answer these questions? ? i need it before 1: 00pm today