Image Alignment

Its because of your CSS here:

.blog-alternate-small #primary article:nth-child(odd) figure {
    float: left;
    padding-right: 4%;
}

The CSS above is overriding your class .alignright.

https://utahrunningcoach.com/wp-content/themes/accelerate/style.css
It is in your main theme stylesheet.

Try commenting out the float like in the sample below.

.blog-alternate-small #primary article:nth-child(odd) figure {
    /* float: left; */
    padding-right: 4%;
}

You do not float center. There is no such thing. float: none; display: block; text-align: center;