title: How can I update multiple states at a time with useState hook?
body: <p>In functional components, we use useState as opposed to this.setState for classComponents. But as far as I know, you can only set one state at a time with useState, while setState lets you set multiple states at a time, (e.g. this.setState({a1: true, a2: false})).</p>
  <p>Does this mean if you wanted to set two states simultaneously with useState, you'd get a double re-render, which is ineffficient? Is there a way to get around this?</p>