. Determine whether these statements are true or false. a) ∅ ∈ {∅} b) ∅ ∈ {∅,{∅}} c) {∅} ∈ {∅} d) {∅} ∈ {{∅}} e) {∅} ⊂ {∅,{∅}} f ) {{∅}} ⊂ {∅,{∅}} g) {{∅}} ⊂ {{∅},{∅}