N-pole points north: neutral points lie on the equatorial line (broadside position) where equatorial field equals $B_H$.

With $d = 18\ \text{cm} = 0.18\ \text{m}$, $l = 7\ \text{cm} = 0.07\ \text{m}$, $B_H = 0.4\times10^{-4}\ \text{T}$:

Equatorial field: $B = \frac{\mu_0}{4\pi}\frac{M}{(d^2+l^2)^{3/2}}$

$M = \frac{B_H(d^2+l^2)^{3/2}}{10^{-7}} = \frac{0.4\times10^{-4}\times(0.0324+0.0049)^{3/2}}{10^{-7}} \approx 28.80\ \text{J\,T}^{-1}$

Article 19 of the Constitution of Pakistan (1973) reads: “Every citizen shall have the right of freedom of speech and expression, and there shall be freedom of the press, subject to any reasonable restrictions imposed by law in the interest of the glory of Islam or the integrity, security, or defence of Pakistan or any part thereof, friendly relations with foreign states, public order, decency or morality or in relation to the contempt of court, defamation or incitement to an offence.” This is a comprehensive list of permissible restrictions. Critics of Pakistani press law note that the breadth of these restrictions — especially “glory of Islam” and “public order” — gives governments considerable room to restrict media freedom. The Freedom of Information Ordinance 2002, while acknowledging citizens' right to know, was also criticised for its restrictive list of disclosable records and 21-day response timeframe, which were seen as undermining the public's true right of access to government information.

There is considerable debate about what constitutes the world's “first” newspaper. The World Association of Newspapers recognises Relation (France, 1605) as the first newspaper. However, the first titled English-language private newspaper was The Corrant, published in London in 1621. The first American newspaper was Publick Occurrences, published in Boston in 1690, though it was suppressed after a single issue by colonial authorities. The first English daily newspaper was the Daily Courant, founded by Samuel Buckley on 11 March 1702. The question asks for “first regular English-language newspaper” — this refers to The Corrant, London, 1621. Students must carefully distinguish between the first French newspaper (La Gazette, 1631), the first American newspaper (Publick Occurrences, Boston, 1690), and the first English daily (Daily Courant, 1702).

At the point of precipitation: $[\text{Ba}^{2+}][\text{SO}_4^{2-}] = K_{sp} = 1 \times 10^{-10}$

Find $[\text{SO}_4^{2-}]$ in the final mixture:

Moles of SO$_4^{2-}$ added $= 0.050\ \text{L} \times 1\ \text{M} = 0.05\ \text{mol}$

Final volume $= 500\ \text{mL} = 0.5\ \text{L}$

$[\text{SO}_4^{2-}]_{\text{final}} = \dfrac{0.05}{0.5} = 0.1\ \text{M}$

Find $[\text{Ba}^{2+}]$ in the final mixture:

$[\text{Ba}^{2+}]_{\text{final}} = \dfrac{K_{sp}}{[\text{SO}_4^{2-}]} = \dfrac{1\times10^{-10}}{0.1} = 1\times10^{-9}\ \text{M}$

Back-calculate original concentration: Final volume is 10× original Ba$^{2+}$ volume (500 mL total, 450 mL original solution).

Original $[\text{Ba}^{2+}] = 1\times10^{-9} \times \dfrac{500}{450} \approx \mathbf{2\times10^{-9}}\ \text{M}$