. Six concrete posts are used to support a waterfront pier. Each post has dimensions 14 in x 14 in x 15 ft. The average density of the concrete is 2.4 g/cm3. ( 1g = 1 x 10-6 metric ton) a. Calculate the volume of concrete (in m3) needed to make one post.

0.58 m³

Explanation:

14 in (1 ft/12 in) = (14/12) ft

(14/12) ft×(14/12) ft×15 ft = 20.41 ft³ (1 m³/35.3 ft³) = 0.58 m³

african americans demonstrated their newly found freedom by relocating often in search of relatives whom they had been separated from during slavery. others established schools to educate freed people and they built institutions such as churches and political organizations to advocate for their rights.

answer : third trial had the contaminated sample and the correct value for dhrxn should be 1000 kj/mol

explanation :

let us write down the given equations

equation 1 :

equation 2 :

equation 3 :

let us use hess's law to find out which 2 equations can be added to get the third equation.

let us reverse equation 2 and multiply it by 2. the new equation that we get is,

equation 4 :

let us add equation 1 & 4

the above equation is similar to equation 3 but has different value for dhrxn.

therefore third trial had the contaminated sample and the correct value for dhrxn should be 1000 kj/mol